|Sorry that you don't want to install more programs, but we're going to recommend malware scans. Update your real-time anti-malware program and run a full system scan. Quarantine any threats and report back the scan results. Next, download and install Malwarebytes Free, update all available definitions, perform a full scan, clean up the threats, and report back the scan results. Lastly, do the exact same with SuperAntiSpyware. SAS is pretty dramatic when it comes to tracking cookies. Just remove those and don't worry about reporting them here.|
A computer will naturally perform slower as time goes on even if all you're installing are critical Windows updates. Throw in other programs you install, including those set to automatically start and update, and you have a computer that won't be as fast as the day you got it. There are also a huge number of temporary files that Windows and various other programs create that aren't well managed, but you can easily delete with CCleaner (slim). Make sure you use the 64-bit program within the download only if your computer is the 64-bit version. Your automatically supplied system specs say Windows XP, so it's most likely you're not running 64-bit.
On the Windows tab of the Cleaner function, I checkmark everything but Menu order cache, Windows size/location cache, User assist history, and Wipe free space. On the Applications tab, I check everything except those related to anti-malware programs.
It's also worth nothing that Facebook does a poor job in complying with web standards and managing memory. A homepage that freezes is the result of too many external sources that they choose to use for a "better" website.
Apologies if I don't respond to your reply immediately. I don't check this site daily, but you're welcome to PM me as a reminder.